Electric Linear actuators are driven by either an AC or DC motor. This article will highlight the main differences between these two motor types in order to assist you in the selection of the correct linear actuator motor.
AC is typically the choice for high power application such as in large factories because it is easier to convert from higher to lower voltages. It also has less electrical losses when sent over long distances which is why it is used on household power lines.
For lower power applications, you will find a mixture of AC and DC motors. For example, in our homes where the power source is primarily AC you will find fans, washing machines and wired power tools with AC motors. For most mobile applications such as cars or cordless devices, DC is much more common since these applications are powered with a battery which is a DC power source.
There are ways to convert between AC and DC power. In Tesla Motors’ electric cars you will find a DC battery that goes through an inverter to power AC motors. In our homes you have AC from the wall socket which gets turned into DC using a converter (an example of which is our PA-20 control box which combines a converter with bidirectional controls in a simple package). This is very common with automated furniture that use electric linear actuators such as reclining chairs, hospital beds and standing desks.
The speed of the DC motor is proportional to the amount of current through the coils. This means that the DC motor’s speed can be altered using a variety of techniques, the simplest being voltage regulation which can be achieved with a simple resistor or a voltage regulator device such as our AC-14 Speed Controller.
On the other hand, AC motors require the frequency of power input to change. AC motors need what is called a Variable Frequency Drive which will alter the incoming AC frequency. For simple applications this is often quite expensive compared to the simpler solutions available for DC motors.